<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
<style>
#myDIV 
{
    background-color: coral;
    border: 1px solid;
    padding: 50px;
    color: white;
}
</style>
</head>
<body>

<div id="myDIV"> div 元素添加了  onmousemove 事件句柄，在你移动鼠标时会显示随机数。
	<p>点击按钮移除 DIV 的事件句柄。</p>
	<button onclick="removeHandler()" id="myBtn">点我</button>
</div>
<p id="demo"></p>
<script>
document.getElementById("myDIV").addEventListener("mousemove", myFunction);
function myFunction() 
{
    document.getElementById("demo").innerHTML = Math.random();
}
function removeHandler() 
{
    document.getElementById("myDIV").removeEventListener("mousemove", myFunction);
}
</script>

</body>
</html>